Autoimmune pancreatitis (AuP) is a chronic pancreatic inflammation secondary to an underlying autoimmune mechanism. After early reports of a particular type of pancreatitis associated with hypergammaglobulinemia, others asserted that there is an autoimmune mechanism involved in some patients with chronic pancreatitis. In 1995 AuP was first described as a distinct clinical entity. Since then, there have been many documented cases of AuP in Japan, and now, perhaps due to increased awareness, more cases are being reported in Europe and the United States. Herein we present our experience with 3 cases of AuP and we review the relevant literature. These 3 cases demonstrate the difficulties that exist in making the diagnosis of AuP and the impact that the diagnosis can have on patient management.